Bearing in mind that I don't trade in vanity hammers, I'd guess 25-35K. The low req and the fact that it's close enough to max to use combine to push it to about 5x what a 15^50 max ram's hammer would. But it isn't perfect, so the true collectors will have no interest. So I set it at a price range that's comfortable for the "weekend warrior" who farms griffons on an occasional basis and wants a cool looking hammer for PvE.
I would say less, a couple of reasons. One is that hammers are already hard enough to sell. Second, given the obsession with 15>50, it is difficult enough to sell something that is not, and given that this is a hammer, it will be very difficult. Based on this, I would price it at 15k.